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Limiting magnitudes
How much aperture do you need to see a given limiting magnitude?
Here are some figures.
mag cm inch
11.0 5.0 2.0
11.5 6.3 2.5
12.0 7.9 3.1
12.5 10.0 3.9
13.0 12.6 5.0
13.5 15.8 6.2
14.0 20.0 7.9
14.5 25.1 9.9
15.0 31.6 12.4
15.5 39.8 15.7
16.0 50.1 19.7
16.5 63.1 24.8
17.0 79.4 31.3
Formula limit = 7.5 + 5 x log(cm)
Last edited by glenc; 01-01-2007 at 11:00 AM.
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